The problems associated with Rotoform bending of steel pipe have caused major corporations to establish policies which forbid its use.
A multi-national conglomerate, major producer of bulk liquid storage tanks with 16,000 employees is at the forefront of this policy.
In a recent publication the company stated that “the use of “Rotoforming or equal is prohibited for bending of all pipe….”
The process itself is at the root cause of their concerns: it actually induces external wall thinning to create the curvature. This wall thinning is a major concern for anyone using pipe in a pressure pipe or a wear application (bulk material transfer).
Another concern is the inaccurate bend tolerances caused by so many variables in the process. Because the process is inconsistent, it is difficult to produce a uniform batch of bends greater than 90 degrees.
Finally, because the thinning is induced from the inside of the pipe, there can be problems cleaning any internal contamination.